[0001] The present invention relates to a machine for stacking tiles included in the selection
line in ceramics factories.
- PRIOR ART AND DRAWBACKS
[0002] The current market trends in the ceramic tiles sector are oriented toward medium-
/ large-sized formats which typically have dimensions per side ranging from 40cm to
one metre and beyond.
[0003] At present, stacking machines operating according to the prior art are generally
included in the selection lines in the case of large formats; these are shown in a
schematic and simplified manner in FIG.1B; the qualifying features that characterize
the prior art are mainly two:
- the various incoming pieces (P) are retained laterally by the belts (CL) and ejected
by vertically acting strikers (ES) and unloaded onto mobile supports (DR); the pair
of belts (CL) are supported by idle wheels mounted on movable elastic devices (DA)
in a horizontal plane so as to be adapted to the tolerances of the various formats
as shown in a schematic model in FIG. 1C;
- during the stacking phase the tiles are supported by the mobile supports (DR) mounted
on structures (DS) fixed to the lower part of the machine. This construction technique
leads to the following drawbacks:
- possible damage (breaks, chipping, scratches, etc...) in the contact between the tiles
being unloaded and the underlying ones since the ejectors (ES) must operate with considerable
force to overcome the resistance of the belts on the lateral walls of the tiles, above
all with large-size formats;
- possible jamming of pieces at the time of ejection, since the pressure of the belts
varies greatly according to the size of the various pieces;
- high noise levels during operation caused by the impact between the pieces and the
impact of the strikers.
- a position and overall dimensions of the stack collecting devices (DR) such as to
make access to the inside of the machine problematic.
- OBJECTS, ADVANTAGES, ENUNCIATION
[0004] The invention has the object of providing a stacking machine with internal apparatus
having constructive solutions such as to remedy the above-mentioned drawbacks, and
in particular with stacking devices inserted in tubular elements arranged in the upper
part of the machine.
[0005] A further and not least important object of the invention is to have a simpler, more
cost-effective machine with the internal devices arranged in such a way as not to
pose limits to the formats to be stacked.
[0006] These and other objects are achieved by the present invention, mainly comprising
a series of supports with rotating brackets (stacking devices) mounted on vertically
sliding guides and inserted in two horizontal tubular elements set in the upper part
of the machine and by a new system for elastically pushing the wheels of the belts
to improve the tile ejection step.
- LIST OF DRAWINGS
[0007] The stacking machine of the present invention and the advantages thereof will be
better described and illustrated with the aid of the following figures, which show
a typical and non-exclusive embodiment.
- FIG. 1A: simplified schematized perspective view of a module of the machine of the
present invention.
- FIG. 1B: simplified schematized front view of a machine built according to the prior
art.
- FIG. 1C: enlarged detail of FIG. 1B.
- FIG.2A and FIG.2B: side view and plan view from above of a complete stacking machine
of the present invention according to a possible embodiment.
- FIG.3: simplified front view vista of the machine of the present invention.
- FIG.4A, FIG.4B, FIG.4C and FIG.4D: details of some devices of the machine of the present
invention.
- FIG.5A to FIG.7B: sequence of movements of the main devices of the present invention.
- DESCRIPTION OF THE COMPONENTS OF THE INVENTION
[0008] FIG.2A and FIG.2B show a complete stacking machine obtained by combining three modules
internally comprising the same devices for a total of 12 stacking stations; this configuration
can be considered a typical assembly for normal production needs.
[0009] For the sake of illustrative clarity, the main parts of the machine are also shown
in FIG. 1A comprising a perspective view of a single module corresponding to the central
one in FIG.2A; the only substantial differences from the other two outer modules are
the terminal parts of the belts (2L), where pulleys (2P) are present, two of them
idle and two motor-driven by means of the motors (1M); FIG. 1A will also be useful
for clarifying some operating details described below.
[0010] The machine mainly comprises a frame assembly (1) to which two tubular elements (2)
are fixed, arranged symmetrically relative to the longitudinal axis, and inside which
a pre-established number of stacking units (3) are inserted, the number thereof depending
on the commercially foreseen classification; inserted in the lower part of the frame
is a belt conveyor (TC) for removing the stacks and other machines for further processing.
DESCRIPTION OF THE FRAME ASSEMBLY (1)
[0011] FIG.3 shows the stacking machine with the two main devices of the present invention,
the profiled assemblies (2) and the stacking units (3): in the right part they are
shown assembled as during normal operation, while in the left part they are separated
to better highlight their constructive features.
[0012] With reference to FIG.3 and FIG. 1A the frame assembly mainly comprises:
- a bearing structure (1 A) to which the chain conveyor (TC) for removing the completed
stacks is fixed in the lower part;
- a series of endless screws (1 V) and guides (1 G) coupled by means of supports (2Z)
to the profiled assemblies (2) for the support and transverse adjustment thereof;
- a series of motors (1 R) for adjusting the distance between the two profiled assemblies
(2).
DESCRIPTION OF THE PROFILED ASSEMBLIES (2)
[0013] See mainly FIG.4A, FIG.4B and FIG.4C.
[0014] Each assembly is made up of:
- a rectangular shaped profiled metal bar (2A);
- a series of motors (2X) for moving (raising-lowering) the stacking units (3) by means
of the gears (2B); said gears engage with the racks (3A) described in the subsequent
unit;
- a series of guides (2C) fixed to the plates (2D), which are in turn fixed to the profiled
bar (2A); the sliding blocks (3B) belonging to the unit (3) slide inside the guide
(2C);
- a series of cam-shaped plates (2H) fixed to the lower part of the profiled bar (2A)
to support the rotating lever (3D), each of which bears inside it an idle roller (2T);
mechanical blocks (2S) are inserted in the inside part of the plates to delimit the
rotation of the bracket (3D);
- a series of pistons (2E) fixed to the profiled bar (2A) and positioned aligned with
the stacking units (3) they are coupled with;
- a belt (2L) held in position by a series of idle wheels (2R); the wheels are supported
with the possibility of oscillating movements around the fastening elements (2V) via
the blocks (2F) and elastic plates (2G).
DESCRIPTION OF THE STACKING UNIT (3)
[0015] See mainly FIG.4A and FIG.4B.
[0016] Each unit is made up of:
- a bearing profiled bar (3C) to which a sliding block (3B) and a rack (3A) are fixed;
- a rotating bracket (3D) pivoted on the profiled bar (3C) in (3G); the bracket is coated
with a layer of rubber (3E) on the upper end thereof;
- a cylindrically shaped counterweight (3P) pivoted on the lower end of the bracket
(3D) with the possibility of rotating in (3V);
- a pin (3R) passing through the counterweight (3P) and pivoted with the possibility
of rotating in (3N) ;
- a spring (3M) inserted in the pin (3R) with the ends thereof pressing toward the counterweight
on one side and toward the pin-hinge (3N) on the other.
[0017] As already partially mentioned, there is a pair of stackers per stacking station,
aligned and arranged symmetrically relative to the longitudinal axis of the machine.
- DESCRIPTION OF OPERATION
[0018] The operation of the stacker is shown by the sequence of figures 5, 6 and 7; as the
machine is symmetrical, for the sake of illustrative clarity only the part with the
devices on the left side is shown.
[0019] FIG.5A shows the machine at the start of the cycle: a tile (P) is passing, supported
by the belts (2L); the stacker (3), still empty, has the supporting bracket (3D) in
a low position, ready to receive tiles.
[0020] In FIG.5B the ejector (2E) is about to unload a tile (one may note the rod completely
outside the piston) onto a nearly completed stack composed of three pieces; the stacking
unit had previously been lowered by an amount equivalent to the thickness of the formed
stack.
[0021] At the moment of ejection the parts (2G) and (2F), which push the wheels laterally
on the belt, tend to open as shown in greater detail in FIG.4C and FIG.4D. In particular,
FIG.4D shows the tendency of the wheels to rotate; this movement of rotation (allowed
by the introduction of a leaf spring (2G) fixed in (2V)) at the moment the piece is
being ejected tends to loosen the grip on the piece and facilitate the ejection thereof.
[0022] When the stack is completed, see FIG.6A, the stacking unit descends in order to deposit
the stack (PL) on the conveyor (TC); subsequently, and without stopping its downward
movement, the stacker descends further until enabling the lever (3D) to be raised
by the action of the counterweight (3P) and of the spring (3M) as shown in FIG.6B.
[0023] In this position the lever (3D) is not in interference with the stack (PL) just deposited,
the stacking unit can thus rise again as shown in FIG.7A; this figure shows the moment
at which the wheel (3F) enters into contact with the cam (2H) in such a way as to
rotate the bracket (3D) in order to bring it back into the operating position, ready
for a subsequent loading step. FIG.7B shows the stacker in a stand-by position, waiting
for a new loading cycle without tiles in proximity, and with the springs (2G) of the
presser of the wheels (2R) in a neutral position, adherent to the inner part of the
profiled bar.
- ENUNCIATION OF THE INVENTIVE CONCEPTS
[0024] The advantages of the machine of the present invention are now evident, and in particular:
- the possible damage caused by the contact between the tiles at the moment of ejection
is minimized by the fact that in the ejection phase the belts (2L) tend to move away,
thus decreasing their pressure on the lateral walls of the tiles; in practice, this
means a lower force in the action of the pistons (2E) compared to the prior art and
a lower speed of impact with the underlying stack; the same reasons apply as regards
jamming and noise;
- the arrangement of the ejector units inserted in the profiled bars in the upper part
leaves the lateral parts of the machine completely free, as also shown in the first
module in FIG.2A.
[0025] The invention thus conceived is susceptible of numerous modifications or variants,
all falling within the scope of the inventive concept; furthermore, all of the details
can be replaced by other technically equivalent elements.
1. A machine for stacking ceramic tiles, mainly comprising a frame assembly (1), two
tubular elements (2) arranged symmetrically relative to the longitudinal axis, a plurality
of stacking units (3) mounted inside the tubular elements (2) and a conveyor (TC)
for removing the stacks which is mounted in the lower part of the frame.
2. The machine according to claim (1),
characterized in that the frame assembly (1) mainly comprises:
- a bearing structure (1A) to which the chain conveyor (TC) is fixed in the lower
part;
- a series of endless screws (1 V), supports (2Z) and guides (1 G) connected to the
profiled assemblies (2) for the support and transverse adjustment thereof;
- a series of motors (1 R) for adjusting the distance between the two profiled assemblies
(2).
3. The machine according to claim (1),
characterized in that each tubular assembly (2) mainly comprises:
- a rectangular shaped profiled metal bar (2A);
- a series of motors (2X) for moving (raising-lowering) the stacking units (3) by
means of gears (2B);
- a series of guides (2C) fixed to the plates (2D), which are in turn fixed to the
profiled bar (2A);
- a series of cam-shaped plates (2H) fixed to the lower part of the profiled bar (2A),
each of which bears inside it an idle roller (2T) and a mechanical block (2S) for
delimiting the rotation of the bracket (3D);
- a series of ejector pistons (2E) fixed to the profiled bar (2A) and positioned aligned
with the stacking units (3) they are coupled with;
- a tile support belt (2L) held in position by a series of elastic dampening devices,
each of which consists of an idle wheel (2R), a block (2F), and an elastic plate (2G)
fixed to the profiled bar (2A) by means of a bolt (2V).
4. The machine according to claim (1),
characterized in that each stacking unit (3) mainly comprises:
- a bearing profiled bar (3C), a sliding block (3B) and a rack (3A);
- a rotating bracket (3D) pivoted on the profiled bar (3C) in (3G); the bracket is
coated with a layer of rubber (3E) on the upper end thereof;
- a cylindrically shaped counterweight (3P) pivoted on the lower end of the bracket
(3D) with the possibility of rotating in (3V);
- a pin (3R) passing through the counterweight (3P) and pivoted with the possibility
of rotating in (3N);
- a spring (3M) inserted in the pin (3R).
5. The machine according to claim (1), characterized in that the stacking units (3) and tubular assemblies (2) are mounted in the upper part of
the frame (1) so that when said stackers are completely raised they leave the sides
of the machine free.